F5 NGINX: buffer overflow
Medium6.9CVE-2026-90439 · Published Sep 15, 2026 · updated Sep 18, 2026
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_v3_module module. When using HTTP/3 with OpenSSL versions <= OpenSSL 3.5.0 under certain configurations, a limited heap buffer overflow could happen while processing a TLS handshake. This can happen in a non-deterministic manner that is beyond the attacker's control. This may cause a heap buffer overflow in the NGINX worker process leading to a restart and/or limited data corruption. Impact: This vulnerability may allow remote attackers to cause a denial-of-service (DoS) on the NGINX system or limited data corruption. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| NGINX Open Source Product | >= 1.29.2, < 1.31.6 | 1.31.6 |
| >= 1.30.4, < 1.30.5 | 1.30.5 | |
| NGINX Plus Product | >= 37.1.0.1, < 37.1.1.2 | 37.1.1.2 |
| >= 37.0.0.1, < 37.0.6.2 | 37.0.6.2 |
Details and references
- CVSS 4.0
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-122
More F5 advisories
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|---|---|---|---|
| Sep 22 | F5 BIG-IP: remote code execution | Critical9.3 | Hotfix-BIGIP-21.1.0.2.0.30.22-ENG+2 more |
| Sep 2 | F5 NGINX JavaScript: out-of-bounds write | Critical9.2 | 1.0.1 |
| Sep 2 | When NGINX Ingress Controller is configured with Ingress annotations | High8.7 | 5.6.0+1 more |
| Sep 2 | F5 NGINX JavaScript: denial of service | High8.7 | 1.0.1 |
| Sep 2 | F5 BIG-IP: attacker could spoof error messages Impact: An attacker may | Low2.3 | 21.1.0.1+3 more |
| Sep 2 | Description: When NGINX Plus is configured as the data plane for NGINX Gateway... | High8.6 | 2.6.8 |